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Abstract:

A liquid ejecting head includes a plurality of liquid ejecting modules
each of which includes a plurality of unit heads each configured to eject
liquid from a plurality of nozzles, and a first fixing plate having a
first surface where the plurality of unit heads are fixed; and a second
fixing plate having a base portion fixed to a second surface of the first
fixing plate of the plurality of liquid ejecting modules, the second
surface located on the side opposite to the first surface, and the base
portion overlapping a gap between the adjacent liquid ejecting modules.

Claims:

1. A liquid ejecting head comprising: a plurality of liquid ejecting
modules each of which includes a plurality of unit heads each configured
to eject liquid from a plurality of nozzles, and a first fixing plate
having a first surface where the plurality of unit heads are fixed; and a
second fixing plate having a base portion fixed to a second surface of
the first fixing plate of the plurality of liquid ejecting modules, the
second surface located on the side opposite to the first surface, and the
base portion overlapping a gap between the adjacent liquid ejecting
modules.

2. The liquid ejecting head according to claim 1, wherein a first opening
portion corresponding to the unit head is formed in the first fixing
plate, wherein a second opening portion corresponding to the unit head is
formed in the second fixing plate, and wherein, in a plan view, the size
of the second opening portion is greater than that of the first opening
portion.

3. The liquid ejecting head according to claim 1, wherein the plurality
of liquid ejecting modules are aligned in a first direction, and wherein
the second fixing plate includes a side wall portion which extends from a
peripheral edge of the base portion, which extends in the first
direction, to each liquid ejecting module side and overlaps a gap between
the adjacent liquid ejecting modules.

4. The liquid ejecting head according to claim 3, wherein an angle
between the side wall portion and the base portion is an obtuse angle.

5. The liquid ejecting head according to claim 1, further comprising: a
support body which supports the plurality of liquid ejecting modules,
wherein the second fixing plate is fixed to the support body.

6. The liquid ejecting head according to claim 1, wherein a thickness of
the second fixing plate is greater than that of the first fixing plate.

7. The liquid ejecting head according to claim 1, wherein a thickness of
the first fixing plate is greater than that of the second fixing plate.

8. A liquid ejecting apparatus comprising: the liquid ejecting head
according to claim 1.

9. A liquid ejecting apparatus comprising: the liquid ejecting head
according to claim 2.

10. A liquid ejecting apparatus comprising: the liquid ejecting head
according to claim 3.

11. A liquid ejecting apparatus comprising: the liquid ejecting head
according to claim 4.

12. A liquid ejecting apparatus comprising: the liquid ejecting head
according to claim 5.

13. A liquid ejecting apparatus comprising: the liquid ejecting head
according to claim 6.

14. A liquid ejecting apparatus comprising: the liquid ejecting head
according to claim 7.

15. The liquid ejecting head according to claim 1, wherein the liquid
ejecting module includes a casing body configured to support the
plurality of unit heads, wherein a variation in first gaps is smaller
than a variation in second gaps, the first gaps defined between the unit
heads and the first surface, the second gaps defined between the unit
heads and the casing body.

16. The liquid ejecting head according to claim 1, further comprising: a
support body configured to support the plurality of liquid ejecting
modules, wherein a variation in third gaps is smaller than a variation in
fourth gaps, the third gaps defined between the liquid ejecting modules
and the base portion, the fourth gaps defined between the liquid ejecting
modules and the support body.

[0003] The present invention relates to a technology of ejecting liquid,
such as ink.

[0004] 2. Related Art

[0005] Hitherto, a technology of ejecting liquid, such as ink, from a
plurality of nozzles has been proposed. A liquid ejecting module (in
other words, a head unit) having a structure in which a plurality of
heads are fixed to one surface of a common fixing plate is disclosed in,
for example, JP-A-2005-96419. The other surface of the fixing plate is
fixed to a cover head for protecting each head.

[0006] In a case of the configuration of JP-A-2005-96419, to expand a
distribution range of a plurality of nozzles, it is necessary to arrange
a plurality of liquid ejecting modules. However, in a case of the
configuration in which a plurality of liquid ejecting modules are
arranged, liquid can enter a gap between adjacent liquid ejecting
modules. Furthermore, there is a possibility that liquid staying in the
gap between the liquid ejecting modules may adhere to a medium, such as a
printing paper sheet.

SUMMARY

[0007] An advantage of some aspects of the invention is to prevent liquid
from entering a gap between liquid ejecting modules.

Aspect 1

[0008] According to Aspect 1, there is provided a liquid ejecting head
including: a plurality of liquid ejecting modules each of which has a
plurality of unit heads each configured to eject liquid from a plurality
of nozzles, and a first fixing plate having a first surface where the
plurality of unit heads are fixed; and a second fixing plate having a
base portion fixed to a second surface of the first fixing plate of the
plurality of liquid ejecting modules, the second surface located on the
side opposite to the first surface, the base portion overlapping a base
portion that overlaps a gap between the adjacent liquid ejecting modules.
In this case, the base portion of the second fixing plate overlaps the
gap between the liquid ejecting modules, and thus the liquid can be
prevented from entering the gap. Furthermore, the plurality of unit heads
are fixed to the first surface of the first fixing plate and the second
surface on the side opposite to the first surface is fixed to the second
fixing plate. Accordingly, there is an advantage in that the positions of
the respective unit heads can be set to the plurality of liquid ejecting
modules with high accuracy, compared to, for example, a configuration in
which the plurality of liquid ejecting modules are fixed to a reference
surface on the side opposite to the first fixing plate with the
respective unit heads interposed therebetween.

Aspect 2

[0009] In the liquid ejecting head according to Aspect 2, a first opening
portion corresponding to the unit head may be formed in the first fixing
plate, a second opening portion corresponding to the unit head may be
formed in the second fixing plate, and, in a plan view, the size of the
second opening portion may be greater than that of the first opening
portion. In this case, in a plan view, the size of the second opening
portion is greater than that of the first opening portion. Thus, there is
an advantage in that, even when an error occurs in the position of each
liquid ejection module in relation to the second fixing plate, a
possibility that a part of the first opening portion or the entirety of
the first opening portion may be closed by the second fixing plate can be
reduced.

Aspect 3

[0010] In the liquid ejecting head according to Aspect 3, the plurality of
liquid ejecting modules may be aligned in a first direction, and the
second fixing plate may include a side wall portion which extends from a
peripheral edge of the base portion, which extends in the first
direction, to each liquid ejecting module side and may overlap a gap
between the adjacent liquid ejecting modules. In this case, the side wall
portion of the second fixing plate overlaps the gap between the
respective liquid ejecting modules. Thus, the above-described effect that
the liquid can be prevented from entering the gap is particularly
significant.

Aspect 4

[0011] In the liquid ejecting head according to Aspect 4, an angle between
the side wall portion and the base portion may be an obtuse angle. In
this case, the angle between the side wall portion and the base portion
is an obtuse angle. Thus, when a target which receives the liquid ejected
by the liquid ejecting head reaches the side wall portion, the target
receiving the ejected liquid can be guided (in other words, induced) to
the base portion side along the side wall portion. Accordingly, there is
an advantage in that a possibility that movement of the target receiving
the ejected liquid may be hindered by the side wall portion and a
possibility that deformation of the target receiving the ejected liquid
may occur due to collision between the target receiving the ejected
liquid and the side wall portion can be reduced.

Aspect 5

[0012] The liquid ejecting head according to Aspect 5 may further include
a support body which supports the plurality of liquid ejecting modules,
and the second fixing plate may be fixed to the support body. In this
case, the second fixing plate is fixed to the support body which supports
the plurality of liquid ejecting modules (in other words, the mechanical
strength of the second fixing plate is reinforced). Thus, deformation of
the second fixing plate can be prevented.

Aspect 6 and Aspect 7

[0013] In the liquid ejecting head according to Aspect 6, a thickness of
the second fixing plate may be greater than that of the first fixing
plate. In this case, the thickness of the second fixing plate is greater
than that of the first fixing plate, and thus there is an advantage in
that it is easy for the second fixing plate to have the mechanical
strength necessary to support the plurality of liquid ejecting modules.
Furthermore, in the liquid ejecting head according to Aspect 7, a
thickness of the first fixing plate may be greater than that of the
second fixing plate. In this case, the thickness of the second fixing
plate is less than that of the first fixing plate, and thus the gap
between the nozzles of each unit head and the target receiving the
ejected liquid is reduced. Accordingly, there is an advantage in that an
error in a liquid landing position can be reduced in relation to the
target receiving the ejected liquid.

Aspect 8

[0014] According to Aspect 8 of the invention, there is provided a liquid
ejecting head including the above-described liquid ejecting head. A
preferred example of the liquid ejecting apparatus is a printing
apparatus which ejects ink onto the medium, such as a printing paper
sheet. However, the use of the liquid ejecting apparatus according to the
invention is not limited to printing.

BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The invention will be described with reference to the accompanying
drawings, wherein like numbers reference like elements.

[0016] FIG. 1 is a configuration view of a printing apparatus according to
Embodiment 1 of the invention.

[0017] FIG. 2 is an exploded perspective view of a liquid ejecting head.

[0018] FIG. 3 is a cross-sectional view taken along the line III-III of
FIG. 2.

[0019] FIG. 4 is a cross-sectional view taken along the line IV-IV of FIG.
2.

[0020] FIG. 5 is a plan view of a part of the liquid ejecting head, which
is a surface facing a medium.

[0021] FIG. 6 is a cross-sectional view and a plan view for explaining
each opening portion of a fixing plate.

[0022] FIG. 7 is an explanatory view of a comparative example.

[0023] FIG. 8 is a process drawing illustrating a manufacturing method of
the liquid ejecting head of Embodiment 1.

[0024] FIG. 9 is an exploded perspective view of a liquid ejecting head
according to Embodiment 2.

[0025] FIG. 10 is a cross-sectional view taken along the line X-X of FIG.
9.

[0026] FIG. 11 is an explanatory view of the thickness of each fixing
plate of a modification example.

DESCRIPTION OF EXEMPLARY EMBODIMENTS

Embodiment 1

[0027] FIG. 1 is a partial configuration view of an ink jet type printing
apparatus 10 according to Embodiment 1 of the invention. The printing
apparatus 10 of Embodiment 1 is a liquid ejecting apparatus which ejects,
onto a medium (in other words, a target receiving ejected ink) 12, such
as a printing paper sheet, ink as an example of liquid. The printing
apparatus 10 of Embodiment 1 includes a controller 22, a transporting
mechanism 24, and a liquid ejecting head 26. A liquid container (in other
words, a cartridge) 14 in which ink is stored is mounted on the printing
apparatus 10.

[0028] The controller 22 controls all components of the printing apparatus
10. The transporting mechanism 24 transports a medium 12 in a Y
direction, in accordance with control by the controller 22. The liquid
ejecting head 26 ejects, onto the medium 12, the ink supplied from the
liquid container 14, in accordance with the control by the controller 22.
The liquid ejecting head 26 of Embodiment 1 is a line head which extends
in an X direction crossing (generally, perpendicular to) the Y direction.
The liquid ejecting head 26 ejects the ink onto the medium 12 while the
medium 12 is transported by the transporting mechanism 24, in such a
manner that a predetermined image is formed on a surface of the medium
12. Hereinafter, a direction perpendicular to an X-Y plane (which is a
plane parallel to the surface of the medium 12) will be referred to as a
Z direction. An ink ejection direction (in other words, a lower side in a
vertical direction) by the liquid ejecting head 26 corresponds to the Z
direction.

[0029] FIG. 2 is an exploded perspective view of the liquid ejecting head
26. The liquid ejecting head 26 of Embodiment 1 includes a support body
32, a fixing plate 34, and a plurality (which is four, in Embodiment 1)
of liquid ejecting modules 36, as illustrated in FIG. 2. The support body
32 is a structure body (in other words, a frame) which supports the
plurality of liquid ejecting modules 36. The support body 32 is formed
by, for example, diecast molding of a metal material or injection molding
of a resin material. The plurality of liquid ejecting modules 36 are
supported in a portion between the support body 32 and the fixing plate
34, in a state where the liquid ejecting modules 36 are arranged in the X
direction, as illustrated in FIG. 2.

[0030] FIG. 3 is a cross-sectional view (which is a cross-sectional
surface parallel to an X-Z plane) taken along a line III-III of FIG. 2.
FIG. 4 is a cross-sectional view taken along a line IV-IV of FIG. 2. Each
of the plurality of liquid ejecting modules 36 includes a plurality
(which is six, in Embodiment 1) of unit heads 42, a casing body 44, a
flow path body 46, and a fixing plate 48, as illustrated in FIGS. 2 to 4.
The casing body 44 is a structure body which supports the plurality of
unit heads 42. The casing body 44 is formed by, for example, injection
molding of a resin material or diecast molding of a metal material. The
flow path body 46 is a structure body in which a flow path for supplying
the ink stored in the liquid container 14 to each unit head 42 and a
valve structure for opening/closing the flow path or controlling pressure
are formed. The flow path body 46 is provided on a side opposite to the
plurality of unit heads 42, with the support body 32 interposed
therebetween. Furthermore, it can be configured so that the casing body
44 and the flow path body 46 are integrally formed.

[0031] Each unit head 42 is a head chip in which the ink is ejected from a
plurality of nozzles (in other words, ejection holes) N. The unit head 42
of Embodiment 1 includes a main body portion 422 and a nozzle plate 424,
as illustrated in FIGS. 2 to 4. The nozzle plate 424 is a long plate
member on which a plurality of nozzles N are formed. The nozzle plate 424
is fixed to a part of the main body portion 422, which is a surface 426
on a positive side (in other words, the medium 12 side) in a Z direction.
The main body portion 422 of Embodiment 1 includes a plurality (not
illustrated) of groups of pressure chambers and piezoelectric elements
which correspond to, for example, different nozzles N. The piezoelectric
element is oscillated by receiving a driving signal and the pressure in
the pressure chamber is changed, in such a manner that the ink filled
into the pressure chamber is ejected from the respective nozzles N of the
nozzle plate 424.

[0032] FIG. 5 is a plan view of a part of the plurality of liquid ejecting
modules 36, which is a surface facing the medium 12. A plurality of unit
heads 42 of each liquid ejecting module 36 are supported by the casing
body 44, in a state where the unit heads 42 are aligned in the X
direction, as illustrated in FIG. 5. The plurality of nozzles N of each
unit head 42 are aligned in a WA direction in the Z-Y plane. In the X-Y
plane, the WA direction is a direction which non-perpendicularly crosses
both the X direction and the Y direction. Specifically, the WA direction
is inclined with respect to the Y direction at angles equal to or greater
than 30° and equal to or less than 60°. In Embodiment 1,
the plurality of nozzles N are aligned in the WA direction inclined to
the Y direction in which the medium 12 is transported, as described
above. Thus, the practical dot density (in other words, resolution) in
the X direction of the medium 12 can be increased, compared to in a case
where a plurality of nozzles N are aligned in a straight line shape, in
the X direction.

[0033] The fixing plate 48 (in other words, a first fixing plate) of FIG.
2 and the casing body 44 support the plurality of unit heads 42. The
fixing plate 48 of Embodiment 1 includes a base portion 482 and a side
wall portion 484, as illustrated in FIGS. 2 to 4. The base portion 482
has a plate shape of which the thickness is substantially the same over
the entirety of the surface thereof. The side wall portion 484 extends
from each edge side of the base portion 482 to a negative side (in other
words, a first surface 48A side) in the Z direction. A material and a
manufacturing method of the fixing plate 48 are not limited. However, the
fixing plate 48 can be formed by, for example, bending a plate member
formed of a high-rigidity material, such as a stainless steel.

[0034] The base portion 482 of the fixing plate 48 is formed in a shape
(specifically, a parallelogram shape) and a size in which, in a plan
view, the base portion 482 and the plurality of unit heads 42 of one
liquid ejecting module 36 overlap each other, as illustrated in FIGS. 2
and 5. The base portion 482 of Embodiment 1 includes the first surface
48A and a second surface 48B, as illustrated in FIGS. 3 and 4. The first
surface 48A is a surface on the support body 32 side (in other words, the
negative side in the Z direction). The second surface 48B is a surface on
a side (in other words, the fixing plate 34 side) opposite to the first
surface 48A.

[0035] The plurality of unit heads 42 are fixed, using, for example, an
adhesive, to the first surface 48A of the base portion 482, as
illustrated in FIGS. 3 and 4. Specifically, the respective unit heads 42
are fixed to the first surface 48A, in a state where front surfaces 426
(which are the mounting surfaces of the nozzle plate 424) of the main
body portions 422 of the respective unit heads 42 are in close contact
with the first surface 48A of the base portion 482. Accordingly,
Z-direction positions of the plurality of unit heads 42 are determined
with, as a criterion, the first surface 48A of the fixing plate 48.
Furthermore, the plurality of unit heads 42 are fixed to the first
surface 40A shared in common, as described above. As a result, there is
also an advantage in that variation (in other words, variation in a gap
between respective unit heads 42) in a gap between each unit head 42 and
the first surface 40A is reduced, compared to variation in a gap between,
for example, each unit head 42 and the casing body 44.

[0036] An opening portion 486 (in other words, a first opening portion)
corresponding to the plurality of nozzles N of each unit head 42 is
formed in the base portion 482, as illustrated in FIG. 5. Each opening
portions 486 is a through-hole which extends in the WA direction so that
the through-hole extends along the arrangement of the plurality of
nozzles N and allows the plurality of nozzles N to be exposed.
Specifically, in a plan view (when seen from the Z direction), the nozzle
plate 424 of each unit head 42 is located in the opening portions 486.
Peripheral edge portions of the fixing plate 48 are fixed to side
surfaces of the casing body 44, using a fixing unit, such as an adhesive
and a screw.

[0037] The fixing plate 34 (in other words, a second fixing plate) of FIG.
2 and the support body 32 support the plurality of liquid ejecting
modules 36. The fixing plate 34 of Embodiment 1 includes a base portion
342, a side wall portion 344, and a side wall portion 346, as illustrated
in FIGS. 2 to 4. The base portion 342 has a plate shape of which the
thickness is substantially the same over the entirety of the surface
thereof. The side wall portion 344 and the side wall portion 346 extend
from a part of the base portion 342, which is each edge side extending in
the X direction, to a negative side in the Z direction. A material and a
manufacturing method of the fixing plate 34 are not limited. However,
similarly to the fixing plate 48, the fixing plate 34 can be formed by,
for example, bending a plate member formed of a high-rigidity material,
such as stainless steel.

[0038] For convenience, in FIG. 5, the external appearance of the fixing
plate 34 is illustrated by a dot-dash line. The base portion 342 of the
fixing plate 34 is formed in a shape (specifically, a parallelogram shape
extending in the X direction) and a size in which, in a plan view, the
base portion 342 and the plurality of liquid ejecting modules 36 overlap
each other, as can be understood from FIGS. 2 and 5.

[0039] The base portion 342 of Embodiment 1 includes a mounting surface
34A and an ejection surface 34B, as illustrated in FIGS. 3 and 4. The
mounting surface 34A is a surface on the plural liquid ejecting modules
36 side (in other words, the negative side in the Z direction). The
ejection surface 34B is a surface (in other words, a surface facing the
medium 12) on a side opposite to the mounting surface 34A.

[0040] The plurality of liquid ejecting modules 36 are fixed, using, for
example, an adhesive, to the mounting surface 34A of the base portion
342, as illustrated in FIGS. 3 and 4. Specifically, the second surface
48B of the fixing plate 48 of each liquid ejecting module 36 is fixed to
the mounting surface 34A of the base portion 342 of the fixing plate 34,
in a state where the second surface 48B is in close contact with the
mounting surface 34A. Accordingly, Z-direction positions of the plurality
of liquid ejecting modules 36 are determined with, as a criterion, the
mounting surface 34A of the fixing plate 34. Furthermore, the plurality
of liquid ejecting modules 36 (in other words, the second surfaces 48B of
the fixing plate 48) are fixed to the mounting surface 34A shared in
common. As a result, there is also an advantage in that variation (in
other words, variation in a gap between respective liquid ejecting
modules 36) in a gap between each liquid ejecting module 36 and the
mounting surface 34A is reduced, compared to variation in a gap between,
for example, each liquid ejecting module 36 and the support body 32. The
liquid ejecting module 36 is constituted by fixing the plurality of unit
heads 42 to the fixing plate 48 shared in common and the liquid ejecting
head 26 is constituted by fixing the plurality of liquid ejecting modules
36 to the fixing plate 34 shared in common, as described above.

[0041] The side wall portion 344 and the side wall portion 346 of the
fixing plate 34 are fixed to a side surface of the support body 32, as
can be understood from FIGS. 2 and 4. Specifically, the side wall portion
344 and the side wall portion 346 are fixed to the side surfaces of the
support body 32, using a fixing unit, such as an adhesive and a screw.
According to the configuration described above, the fixing plate 34 is
fixed to the support body 32 having a high mechanical strength, and thus
deformation of the fixing plate 34 can be prevented.

[0042] An opening portion 348 (in other words, a second opening portion)
corresponding to the plurality of nozzles N of each unit head 42 of each
liquid ejecting module 36 is formed in the base portion 342 of the fixing
plate 34, as illustrated in FIGS. 2 to 4. Each opening portion 348
extends in the WA direction so that the opening portion 348 extends along
the arrangement of the plurality of nozzles N, similarly to the opening
portions 486. Thus, in a plan view, the opening portion 348 and the
opening portions 486 overlap each other. Accordingly, the plurality of
nozzles N of each unit head 42 are exposed through both the opening
portions 486 of the fixing plate 48 and the opening portion 348 of the
fixing plate 34.

[0043] FIG. 6 is an explanatory view of the relationship between the
opening portions 486 of the fixing plate 48 and the opening portion 348
of the fixing plate 34. In a plan view, the size of the opening portion
348 is larger than that of the opening portions 486, as illustrated in
FIG. 6. Specifically, a length (in other words, an overall length) A2 of
the opening portion 348 in the WA direction is greater (A2>A1) than a
length A1 of the opening portions 486. In addition, a length (in other
words, a width) B2 of the opening portion 348 in a WB direction
perpendicular to the WA direction is greater (B2>B1) than a length B1
of the opening portions 486. According to the configuration described
above, there is an advantage in that, even when an error occurs in the
position of each liquid ejecting module 36 in relation to the fixing
plate 34, a possibility that a part of the opening portions 486 or the
entirety of the opening portions 486 may be closed by the fixing plate 34
is reduced. In other words, a required condition of the positional
accuracy of each liquid ejecting module 36 in relation to the fixing
plate 34 is eased (in other words, the alignment between the respective
liquid ejecting modules 36 is eased).

[0044] A thickness T2 of the fixing plate 34 (in other words, the base
portion 342) is greater (T2>T1) than a thickness T1 of the fixing
plate 48 (in other words, the base portion 482), as illustrated in FIG.
6. Accordingly, when it is assumed that the fixing plate 34 and the
fixing plate 48 are constituted of the same material, the mechanical
strength (in other words, the bending rigidity) of the fixing plate 34 is
greater than that of the fixing plate 48. According to the configuration
described above, there is an advantage in that it is easy for the fixing
plate 34 to have a mechanical strength necessary to support the plurality
of liquid ejecting modules 36, compared to a configuration (for example,
a configuration in which the thickness T2 is less than the thickness T1)
in which the mechanical strength of the fixing plate 34 is less than that
of the fixing plate 48.

[0045] A gap G can be formed in a portion between adjacent liquid ejecting
modules 36 in the X direction, as illustrated in FIGS. 3 and 5.
Specifically, in the portion between the adjacent liquid ejecting modules
36, a space interposed between the outer circumferential surface of the
side wall portion 484 of the fixing plate 48, the side surface of the
casing body 44, and the side surface of the flow path body 46 corresponds
to the gap G. The fixing plate 34 of Embodiment 1 and the gap G between
the respective liquid ejecting modules 36 overlap in the Z direction, as
illustrated in FIG. 3. Specifically, a part of the base portion 342,
which is a portion 34C located in a portion between the respective
opening portions 348, and the gap G overlap in the Z direction.
Furthermore, the side wall portion 344 and the side wall portion 346 of
the fixing plate 34 and the gap G between the respective liquid ejecting
modules 36 overlap in the Y direction, as can be understood from FIG. 5.
In other words, the gap G between the adjacent liquid ejecting modules 36
is closed, in the Z direction, by the base portion 342 and, further, the
gap G is closed, in the Y direction, by both the side wall portion 344
and the side wall portion 346.

[0046] In Embodiment 1, the fixing plate 34 (in other words, the base
portion 342) and the gap G of the respective liquid ejecting modules 36
overlap in the Z direction, as described above, and thus the ink can be
prevented from entering the gap G. Furthermore, the gap G is closed by
the base portion 342. Thus, there is an advantage in that, even when the
medium 12 comes into contact, from the Z direction, with the liquid
ejecting head 26, in a state where the ink stays in, for example, the gap
G, the ink in the gap G does not adhere to the medium 12. Particularly,
in Embodiment 1, the side wall portion 344 and the side wall portion 346
of the fixing plate 34 overlap, in the Y direction, the gap G of the
respective liquid ejecting modules 36. Thus, a special effect that the
ink can be prevented from entering the gap G from the Y direction is
obtained. Furthermore, the side wall portion 344 and the side wall
portion 346 close the gap G from the Y direction. Thus, there is an
advantage in that, even when the medium 12 comes into contact, from the Y
direction, with the liquid ejecting head 26, in a state where the ink
stays in, for example, the gap G, the ink in the gap G does not adhere to
the medium 12.

[0047] Meanwhile, a configuration (hereinafter, referred to as a
"comparative example") in which, when viewed from the liquid ejecting
module 36, the plurality of liquid ejecting modules 36 are fixed to a
surface (hereinafter, referred to as a "reference surface") Q on the
negative side in the Z direction can be conceived as a configuration in
which the plurality of liquid ejecting modules 36 having the plurality of
unit heads 42 fixed to the first surface 48A of the fixing plate 48 are
fixed, as illustrated in, for example, FIG. 7. However, in the
configuration of the comparative example, when an error occurs in the
size of the support body 32 or the flow path body 46 which is located on
the negative side in the Z direction, when viewed from the main body
portion 422 of each unit head 42, there is a problem in that the
Z-direction position of each unit head 42 is different for each liquid
ejecting module 36, as can be understood from FIG. 7. However, in
Embodiment 1, the plurality of unit heads 42 are fixed to the first
surface 48A of the fixing plate 48 and, further, the plurality of liquid
ejecting modules 36 are fixed to the mounting surface 34A of the fixing
plate 34. In other words, the Z-direction positions of the plurality of
unit heads 42 are determined with, as a criterion, the first surface 48A
which is located on the positive side in the Z direction when viewed from
each unit head 42. Furthermore, the Z-direction positions of the
plurality of liquid ejecting modules 36 are determined with, as a
criterion, the mounting surface 34A which is also located on the positive
side in the Z direction when viewed from each unit head 42. Accordingly,
even when an error occurs in the size of each unit head 42, the support
body 32 or the flow path body 46, the Z-direction positions of the
respective unit heads 42 can be set (in other words, can be made to
matched throughout, for example, the plurality of liquid ejecting modules
36) with high accuracy, in relation to the liquid ejecting module 36.
Manufacturing Method of Liquid Ejecting Head 26

[0048] Hereinafter, the manufacturing method (in other words, the
assembling method) of the liquid ejecting head 26 described above will be
described. FIG. 8 is an explanatory view of processes of manufacturing
the liquid ejecting head 26.

[0049] In a process P1 and a process P2, assembling of each liquid
ejecting module 36 is performed. In the process P1 performed at first,
the plurality of unit heads 42 are fixed to the fixing plate 48.
Specifically, the front surface 426 of each unit head 42 is fixed, using,
for example, an adhesive, to the first surface 48A of the base portion
482 of the fixing plate 48, in a state where the position of each unit
head 42 is adjusted in relation to the fixing plate 48 so that each
nozzle N of each unit head 42 is located at a target position.
Accordingly, the Z-direction positions of the plurality of unit heads 42
constituting the liquid ejecting module 36 are determined with the first
surface 48A as a criterion. Specifically, the front surfaces 426 of the
plurality of unit heads 42 are located in the same plane. In the process
P2 following the process P1, the fixing plate 48 is fixed to both the
casing body 44 and the flow path body 46, in a state where the plurality
of unit heads 42 fixed to the fixing plate 48 are accommodated in the
casing body 44. During the processes described above, the liquid ejecting
module 36 is manufactured.

[0050] In a process P3, inspection of the liquid ejecting module 36 is
performed. Specifically, the suitability (in other words,
ejection/non-ejection or the amount of ink ejected) of ink ejection by
the respective nozzles N of each unit head 42 is inspected. The liquid
ejecting module 36 is inspected in a state where the ink is supplied to
each unit head 42 through the flow path body 46, similarly to in a case
of actual use of the printing apparatus 10, as described above.
Furthermore, in a case of the liquid ejecting head 26 in which the
plurality of liquid ejecting modules 36 are mounted on both the support
body 32 and the fixing plate 34, when, for example, one unit head 42 is a
defective unit, the entirety of the liquid ejecting head 26 is determined
as a defective unit. However, in Embodiment 1, failure or non-failure is
determined for each liquid ejecting module 36, and thus there is an
advantage in that a manufacturing cost can be reduced, compared to in a
case where an inspection target is the liquid ejecting head 26.

[0051] In a process P4, the plurality of liquid ejecting modules 36 which
are determined as non-defective units by inspection during the process P3
are fixed to the fixing plate 34. Specifically, the second surface 48B of
the fixing plate 48 of each liquid ejecting module 36 is fixed, using,
for example, an adhesive, to the mounting surface 34A of the base portion
342 of the fixing plate 34. Accordingly, the Z-direction positions of the
plurality of liquid ejecting modules 36 are determined with the mounting
surface 34A as a criterion. Specifically, the second surfaces 48B of the
fixing plates 48 of each liquid ejecting module 36 are located in the
same plane. After the process P4 is performed, the fixing plate 34 is
fixed to the support body 32, in a state where the plurality of the
liquid ejecting modules 36 are accommodated in the support body 32, in
such a manner that the liquid ejecting head 26 of Embodiment 1
illustrated in FIG. 3 is manufactured.

Embodiment 2

[0052] Embodiment 2 of the invention will be described. Furthermore, in
each configuration described below, the reference numerals and letters
which are used in the description of Embodiment 1 are given to components
of which the operations and the functions are the same as those of
Embodiment 1. The details of the configurations of these components will
be appropriately omitted.

[0053] FIG. 9 is an exploded perspective view of the liquid ejecting head
26 of Embodiment 2 and FIG. 10 is a cross-sectional view (in other words,
a view of a cross-sectional surface parallel to a WA-Z plane) taken along
a line X-X of FIG. 9. The shape of the fixing plate 34 of Embodiment 2 is
different from that of Embodiment 1, as illustrated in FIGS. 9 and 10.
Specifically, a part of the fixing plate 34 of Embodiment 2, which is the
side wall portion 344 located on the negative side (in other words, an
upstream side in a transport direction of the medium 12) in the Y
direction, is inclined with respect to the base portion 342.
Specifically, the side wall portion 344 and the base portion 342 are
inclined (in other words, non-perpendicularly cross) at an obtuse angle
θ (90°<θ<180°).

[0054] Embodiment 2 can obtain the same effect as that of Embodiment 1.
Furthermore, in Embodiment 2, the side wall portion 344 and the base
portion 342 cross at the obtuse angle θ. Thus, when the leading
edge of the medium 12 transported from the negative side to the positive
side in the Y direction reaches the side wall portion 344, the medium 12
is guided, along the side wall portion 344, to the ejection surface 34B
side of the fixing plate 34, as illustrated by an arrow a in FIG. 10.
Accordingly, there is an advantage in that a possibility that movement of
the medium 12 may be hindered by the side wall portion 344 and a
possibility that deformation, such as folding, of the medium 12 may occur
due to collision between the medium 12 and the side wall portion 344 can
be reduced.

Modification Examples

[0055] The embodiments described above can be modified in various ways.
Specific modification examples will be described below. Two or more
modification examples which are arbitrarily selected from the examples
described below can be appropriately used in combination as long as they
do not conflict with each other.

[0056] (1) In the embodiments described above, the configuration in which
the thickness T2 of the fixing plate 34 is greater (T2>T1) than the
thickness T1 of the fixing plate 48 is exemplified. However, a
configuration in which the thickness T2 of the fixing plate 34 is less
(T2<T1) than the thickness T1 of the fixing plate 48 can also be
applied, as illustrated in FIG. 11. In a configuration in which a gap (in
other words, a platen gap) between the surface of the medium 12 and the
nozzles N is large, there is a possibility that an ink traveling
direction may change during a period in which the ink ejected from each
nozzle N lands on the surface of the medium 12, and this thus resulting
in an occurrence of an error in the landing position. According to the
configuration of FIG. 11, the thickness T2 of the fixing plate 34 is
reduced, compared to Embodiment 1. Thus, a gap between the nozzles N (in
other words, the surface of the nozzle plate 424) of the unit head 42 and
the surface of the medium 12 is reduced. In other words, the respective
nozzles N can be located closer to the medium 12. Accordingly, there is
an advantage in that an error in the landing position of the ink in
relation to the medium 12 can be reduced.

[0057] (2) In Embodiment 2, the configuration in which a part of the
fixing plate 34, which is the side wall portion 344 located on the
negative side in the Y direction, is inclined with respect to the base
portion 342 is exemplified. However, in addition to the configuration
described above (or instead of the configuration described above), the
configuration in which a part of the fixing plate 34, which is the side
wall portion 346 located on the positive side (in other words, on the
downstream side in the transport direction of the medium 12) in the Y
direction is inclined with respect to the base portion 342 at an obtuse
angle can also be applied. According to the configuration described
above, in a configuration in which, for example, the transport direction
of the medium 12 can be reversed, the medium 12 transported from the
positive side to the negative side in the Y direction can be guided,
along the side wall portion 346, to the ejection surface 34B side of the
fixing plate 34.

[0058] (3) In the embodiments described above, the printing apparatus 10
of a line type in which the plurality of unit heads 42 are aligned over
the entirety of the width of the medium 12 is exemplified. However, the
invention can also be applied to a printing apparatus of a serial type in
which a carriage having the liquid ejecting head 26 mounted thereon
reciprocates in the X direction.

[0059] (4) The ink ejection type of the unit head 42 is not limited to the
above-described type (in other words, a piezo type) using a piezoelectric
element. The invention can also be applied to a liquid ejecting head of a
type (in other words, a thermal type) using a heating element which
causes air bubbles to be generated in the pressure chamber by heating and
changes the pressure of a pressure chamber.

[0060] (5) The printing apparatus 10 exemplified in the embodiments
described above can be applied to various apparatuses, such as a
facsimile machine and a copy machine, other than an apparatus dedicated
to printing. Furthermore, the use of the liquid ejecting apparatus of the
invention is not limited to printing. A liquid ejecting apparatus
ejecting, for example, a colorant solution may be used as a manufacturing
apparatus which forms a color filter for a liquid crystal display device.
Furthermore, a liquid ejecting apparatus ejecting a solution of a
conductive material is used as a manufacturing apparatus which forms
wiring and an electrode of a wiring substrate.